Quinolizidine Alkaloids with Antitomato Spotted Wilt Virus and Insecticidal Activities from the Seeds of R. Br.

As part of our ongoing investigation of pesticide active quinolizidine alkaloids (QAs) from the family Fabaceae, the chemical constituents of the seeds of R. Br. were systematically investigated. Bioassay-guided fractionation and purification of the crude extract led to the isolation of seventeen new QAs (-), including three new naturally occurring compounds (-), along with 15 known compounds (-). Their structures were elucidated by comprehensive spectroscopic data analysis (IR, UV, NMR, and HRESIMS) and quantum chemistry calculations (C NMR and ECD). The antitomato spotted wilt virus activities and insecticidal activities against , (Stal), and of compounds - were screened using the lesion counting method, spray method, and rice-stem dipping method, respectively. Biological tests indicated that compounds , , and displayed significant anti-TSWV activities compared with the positive control ningnanmycin. Compounds , , and showed better insecticidal activities against with LC values of 10.07, 12.07, and 6.56 mg/L, respectively. Moreover, compounds , , and exhibited moderate insecticidal activities against (Stal) with LC values of 37.91, 53.44, and 31.21 mg/L, respectively. Furthermore, compounds and exhibited moderate insecticidal activities against .